class User {
  private String name;

  public User(String name) {
    this.name = name;
  }
  
  public String getName() {
    return name;
  }

  public double getPrice(double roomPrice) {
    return roomPrice; // 默认情况下，普通用户是全价
  }
}

class RegularUser extends User {
  public RegularUser(String name) {
    super(name);
  }
}

class GoldUser extends User {
  public GoldUser(String name) {
    super(name);
  }

  @Override
  public double getPrice(double roomPrice) {
    return roomPrice * 0.8; // 金卡用户是 8 折
  }
}

class SilverUser extends User {
  public SilverUser(String name) {
    super(name);
  }

  @Override
  public double getPrice(double roomPrice) {
    return roomPrice * 0.9; // 银卡用户是 9 折
  }
}

public class HotelBookingSystem {
  public static void main(String[] args) {
    double roomPrice = 100.0; // 房间价格假设为 100

    User regularUser = new RegularUser("Alice");
    System.out.println(regularUser.getName() + "的房价是：" + regularUser.getPrice(roomPrice));

    User goldUser = new GoldUser("Bob");
    System.out.println(goldUser.getName() + "的房价是：" + goldUser.getPrice(roomPrice));

    User silverUser = new SilverUser("Charlie");
    System.out.println(silverUser.getName() + "的房价是：" + silverUser.getPrice(roomPrice));
  }
}